Merge pull request #4033 from ethereum-optimism/sc/ctb-l2oo-genesis-init

feat(ctb): move L2OO genesis setup to init

op-chain-ops/genesis/layer_one.go

@@ -103,6 +103,8 @@ func BuildL1DeveloperGenesis(config *DeployConfig) (*core.Genesis, error) {
 	data, err = l2ooABI.Pack(
 		"initialize",
 		config.L2OutputOracleGenesisL2Output,
+		big.NewInt(0),
+		uint642Big(uint64(config.L1GenesisBlockTimestamp)),
 		config.L2OutputOracleProposer,
 		config.L2OutputOracleOwner,
 	)
@@ -275,10 +277,10 @@ func deployL1Contracts(config *DeployConfig, backend *backends.SimulatedBackend)
 			Name: "L2OutputOracle",
 			Args: []interface{}{
 				uint642Big(config.L2OutputOracleSubmissionInterval),
+				uint642Big(config.L2BlockTime),
 				[32]byte(config.L2OutputOracleGenesisL2Output),
 				big.NewInt(0),
 				uint642Big(uint64(config.L1GenesisBlockTimestamp)),
-				uint642Big(config.L2BlockTime),
 				config.L2OutputOracleProposer,
 				config.L2OutputOracleOwner,
 			},
@@ -337,8 +339,8 @@ func l1Deployer(backend *backends.SimulatedBackend, opts *bind.TransactOpts, dep
 			opts,
 			backend,
 			deployment.Args[0].(*big.Int),
-			deployment.Args[1].([32]byte),
-			deployment.Args[2].(*big.Int),
+			deployment.Args[1].(*big.Int),
+			deployment.Args[2].([32]byte),
 			deployment.Args[3].(*big.Int),
 			deployment.Args[4].(*big.Int),
 			deployment.Args[5].(common.Address),

op-chain-ops/genesis/layer_one_test.go

@@ -55,7 +55,7 @@ func TestBuildL1DeveloperGenesis(t *testing.T) {
 	require.NoError(t, err)
 	require.EqualValues(t, config.L2OutputOracleSubmissionInterval, interval.Uint64())
 
-	startBlock, err := oracle.STARTINGBLOCKNUMBER(callOpts)
+	startBlock, err := oracle.StartingBlockNumber(callOpts)
 	require.NoError(t, err)
 	require.EqualValues(t, 0, startBlock.Uint64())
 

packages/contracts-bedrock/.gas-snapshot

@@ -5,7 +5,7 @@ GasBenchMark_L1StandardBridge_Deposit:test_depositERC20_benchmark_1() (gas: 1122
 GasBenchMark_L1StandardBridge_Deposit:test_depositETH_benchmark_0() (gas: 348176)
 GasBenchMark_L1StandardBridge_Deposit:test_depositETH_benchmark_1() (gas: 112253)
 GasBenchMark_L1StandardBridge_Finalize:test_finalizeETHWithdrawal_benchmark() (gas: 40502)
-GasBenchMark_L2OutputOracle:test_proposeL2Output_benchmark() (gas: 68620)
+GasBenchMark_L2OutputOracle:test_proposeL2Output_benchmark() (gas: 72807)
 GasBenchMark_OptimismPortal:test_depositTransaction_benchmark() (gas: 74956)
 GasBenchMark_OptimismPortal:test_depositTransaction_benchmark_1() (gas: 35693)
 CrossDomainMessenger_Test:testFuzz_baseGas(uint32) (runs: 256, μ: 20196, ~: 20196)
@@ -85,30 +85,30 @@ L2CrossDomainMessenger_Test:test_L2MessengerSendMessage() (gas: 122423)
 L2CrossDomainMessenger_Test:test_L2MessengerTwiceSendMessage() (gas: 134632)
 L2CrossDomainMessenger_Test:test_L2MessengerXDomainSenderReverts() (gas: 10568)
 L2CrossDomainMessenger_Test:test_L2MessengerxDomainMessageSenderResets() (gas: 52615)
-L2OutputOracleTest:testCannot_ProposeWithUnmatchedBlockhash() (gas: 26776)
-L2OutputOracleTest:testCannot_constructWithBadTimestamp() (gas: 50351)
-L2OutputOracleTest:testCannot_deleteL2Outputs_afterLatest() (gas: 194584)
-L2OutputOracleTest:testCannot_deleteL2Outputs_ifNotOwner() (gas: 18871)
-L2OutputOracleTest:testCannot_deleteL2Outputs_nonExistent() (gas: 86711)
-L2OutputOracleTest:testCannot_proposeEmptyOutput() (gas: 24085)
-L2OutputOracleTest:testCannot_proposeFutureTimetamp() (gas: 26043)
-L2OutputOracleTest:testCannot_proposeL2OutputIfNotProposer() (gas: 23515)
-L2OutputOracleTest:testCannot_proposeOnWrongFork() (gas: 26371)
-L2OutputOracleTest:testCannot_proposeUnexpectedBlockNumber() (gas: 25955)
-L2OutputOracleTest:test_changeProposer() (gas: 47212)
-L2OutputOracleTest:test_computeL2Timestamp() (gas: 30430)
-L2OutputOracleTest:test_constructor() (gas: 45691)
-L2OutputOracleTest:test_deleteOutputs_multipleOutputs() (gas: 203841)
-L2OutputOracleTest:test_deleteOutputs_singleOutput() (gas: 94524)
-L2OutputOracleTest:test_getL2Output() (gas: 84525)
-L2OutputOracleTest:test_latestBlockNumber() (gas: 76229)
-L2OutputOracleTest:test_nextBlockNumber() (gas: 15120)
-L2OutputOracleTest:test_proposeWithBlockhashAndHeight() (gas: 75035)
-L2OutputOracleTest:test_proposingAnotherOutput() (gas: 76837)
-L2OutputOracleTest:test_updateOwner() (gas: 36063)
-L2OutputOracleUpgradeable_Test:test_cannotInitImpl() (gas: 17381)
-L2OutputOracleUpgradeable_Test:test_cannotInitProxy() (gas: 22376)
-L2OutputOracleUpgradeable_Test:test_initValuesOnProxy() (gas: 38217)
+L2OutputOracleTest:testCannot_ProposeWithUnmatchedBlockhash() (gas: 31173)
+L2OutputOracleTest:testCannot_constructWithBadTimestamp() (gas: 73077)
+L2OutputOracleTest:testCannot_deleteL2Outputs_afterLatest() (gas: 199643)
+L2OutputOracleTest:testCannot_deleteL2Outputs_ifNotOwner() (gas: 18827)
+L2OutputOracleTest:testCannot_deleteL2Outputs_nonExistent() (gas: 91042)
+L2OutputOracleTest:testCannot_proposeEmptyOutput() (gas: 28482)
+L2OutputOracleTest:testCannot_proposeFutureTimetamp() (gas: 30440)
+L2OutputOracleTest:testCannot_proposeL2OutputIfNotProposer() (gas: 27703)
+L2OutputOracleTest:testCannot_proposeOnWrongFork() (gas: 30768)
+L2OutputOracleTest:testCannot_proposeUnexpectedBlockNumber() (gas: 30143)
+L2OutputOracleTest:test_changeProposer() (gas: 47124)
+L2OutputOracleTest:test_computeL2Timestamp() (gas: 37255)
+L2OutputOracleTest:test_constructor() (gas: 50016)
+L2OutputOracleTest:test_deleteOutputs_multipleOutputs() (gas: 209200)
+L2OutputOracleTest:test_deleteOutputs_singleOutput() (gas: 99133)
+L2OutputOracleTest:test_getL2Output() (gas: 89416)
+L2OutputOracleTest:test_latestBlockNumber() (gas: 80604)
+L2OutputOracleTest:test_nextBlockNumber() (gas: 15121)
+L2OutputOracleTest:test_proposeWithBlockhashAndHeight() (gas: 79432)
+L2OutputOracleTest:test_proposingAnotherOutput() (gas: 81212)
+L2OutputOracleTest:test_updateOwner() (gas: 36019)
+L2OutputOracleUpgradeable_Test:test_cannotInitImpl() (gas: 21727)
+L2OutputOracleUpgradeable_Test:test_cannotInitProxy() (gas: 26731)
+L2OutputOracleUpgradeable_Test:test_initValuesOnProxy() (gas: 42544)
 L2OutputOracleUpgradeable_Test:test_upgrading() (gas: 180457)
 L2StandardBridge_Test:test_cannotWithdrawEthWithoutSendingIt() (gas: 21749)
 L2StandardBridge_Test:test_finalizeBridgeETH_incorrectValueReverts() (gas: 23733)
@@ -150,23 +150,23 @@ OptimismPortalUpgradeable_Test:test_initialize_cannotInitImpl_reverts() (gas: 10
 OptimismPortalUpgradeable_Test:test_initialize_cannotInitProxy_reverts() (gas: 15767)
 OptimismPortalUpgradeable_Test:test_params_initValuesOnProxy_success() (gas: 16010)
 OptimismPortalUpgradeable_Test:test_upgradeToAndCall_upgrading_success() (gas: 180435)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputRootChanges_reverts() (gas: 195163)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputTimestampIsNotFinalized_reverts() (gas: 197363)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputRootChanges_reverts() (gas: 199477)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputTimestampIsNotFinalized_reverts() (gas: 201677)
 OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifWithdrawalNotProven_reverts() (gas: 39634)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifWithdrawalProofNotOldEnough_reverts() (gas: 192839)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onInsufficientGas_reverts() (gas: 193168)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onRecentWithdrawal_reverts() (gas: 173211)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReentrancy_reverts() (gas: 233445)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReplay_reverts() (gas: 235161)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_provenWithdrawalHash_success() (gas: 227144)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_targetFails_fails() (gas: 329759)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_timestampLessThanL2OracleStart_reverts() (gas: 193617)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onInvalidOutputRootProof_reverts() (gas: 83389)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifWithdrawalProofNotOldEnough_reverts() (gas: 197153)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onInsufficientGas_reverts() (gas: 195340)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onRecentWithdrawal_reverts() (gas: 175375)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReentrancy_reverts() (gas: 235617)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReplay_reverts() (gas: 239939)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_provenWithdrawalHash_success() (gas: 231608)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_targetFails_fails() (gas: 334223)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_timestampLessThanL2OracleStart_reverts() (gas: 195767)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onInvalidOutputRootProof_reverts() (gas: 85539)
 OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onSelfCall_reverts() (gas: 50754)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_oninvalidWithdrawalProof_reverts() (gas: 136647)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_replayProveChangedOutputRoot_success() (gas: 276836)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_replayProve_reverts() (gas: 188898)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_validWithdrawalProof_success() (gas: 179214)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_oninvalidWithdrawalProof_reverts() (gas: 138797)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_replayProveChangedOutputRoot_success() (gas: 279136)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_replayProve_reverts() (gas: 191198)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_validWithdrawalProof_success() (gas: 181364)
 OptimismPortal_Test:test_OptimismPortalConstructor() (gas: 17298)
 OptimismPortal_Test:test_OptimismPortalReceiveEth_success() (gas: 127483)
 OptimismPortal_Test:test_depositTransaction_NoValueContract_success() (gas: 76706)
@@ -178,7 +178,7 @@ OptimismPortal_Test:test_depositTransaction_withEthValueAndContractContractCreat
 OptimismPortal_Test:test_depositTransaction_withEthValueAndEOAContractCreation_success() (gas: 75852)
 OptimismPortal_Test:test_depositTransaction_withEthValueFromContract_success() (gas: 83370)
 OptimismPortal_Test:test_depositTransaction_withEthValueFromEOA_success() (gas: 83964)
-OptimismPortal_Test:test_isBlockFinalized_success() (gas: 104802)
+OptimismPortal_Test:test_isBlockFinalized_success() (gas: 109865)
 OptimismPortal_Test:test_simple_isBlockFinalized_success() (gas: 24142)
 Proxy_Test:test_clashingFunctionSignatures() (gas: 101347)
 Proxy_Test:test_implementationKey() (gas: 20887)

packages/contracts-bedrock/.storage-layout

@@ -64,25 +64,29 @@
 ➡ contracts/L1/L2OutputOracle.sol:L2OutputOracle
 =======================
 
-+-------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------+
-| Name              | Type                                            | Slot | Offset | Bytes | Contract                                       |
-+==============================================================================================================================================+
-| _initialized      | uint8                                           | 0    | 0      | 1     | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
-|-------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
-| _initializing     | bool                                            | 0    | 1      | 1     | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
-|-------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
-| __gap             | uint256[50]                                     | 1    | 0      | 1600  | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
-|-------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
-| _owner            | address                                         | 51   | 0      | 20    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
-|-------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
-| __gap             | uint256[49]                                     | 52   | 0      | 1568  | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
-|-------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
-| proposer          | address                                         | 101  | 0      | 20    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
-|-------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
-| latestBlockNumber | uint256                                         | 102  | 0      | 32    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
-|-------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
-| l2Outputs         | mapping(uint256 => struct Types.OutputProposal) | 103  | 0      | 32    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
-+-------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------+
++---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------+
+| Name                | Type                                            | Slot | Offset | Bytes | Contract                                       |
++================================================================================================================================================+
+| _initialized        | uint8                                           | 0    | 0      | 1     | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
+|---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
+| _initializing       | bool                                            | 0    | 1      | 1     | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
+|---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
+| __gap               | uint256[50]                                     | 1    | 0      | 1600  | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
+|---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
+| _owner              | address                                         | 51   | 0      | 20    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
+|---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
+| __gap               | uint256[49]                                     | 52   | 0      | 1568  | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
+|---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
+| startingBlockNumber | uint256                                         | 101  | 0      | 32    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
+|---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
+| startingTimestamp   | uint256                                         | 102  | 0      | 32    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
+|---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
+| proposer            | address                                         | 103  | 0      | 20    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
+|---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
+| latestBlockNumber   | uint256                                         | 104  | 0      | 32    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
+|---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------|
+| l2Outputs           | mapping(uint256 => struct Types.OutputProposal) | 105  | 0      | 32    | contracts/L1/L2OutputOracle.sol:L2OutputOracle |
++---------------------+-------------------------------------------------+------+--------+-------+------------------------------------------------+
 
 =======================
 ➡ contracts/L1/OptimismPortal.sol:OptimismPortal

packages/contracts-bedrock/contracts/L1/L2OutputOracle.sol

@@ -22,19 +22,19 @@ contract L2OutputOracle is OwnableUpgradeable, Semver {
     uint256 public immutable SUBMISSION_INTERVAL;
 
     /**
-     * @notice The number of the first L2 block recorded in this contract.
+     * @notice The time between L2 blocks in seconds.
      */
-    uint256 public immutable STARTING_BLOCK_NUMBER;
+    uint256 public immutable L2_BLOCK_TIME;
 
     /**
-     * @notice The timestamp of the first L2 block recorded in this contract.
+     * @notice The number of the first L2 block recorded in this contract.
      */
-    uint256 public immutable STARTING_TIMESTAMP;
+    uint256 public startingBlockNumber;
 
     /**
-     * @notice The time between L2 blocks in seconds.
+     * @notice The timestamp of the first L2 block recorded in this contract.
      */
-    uint256 public immutable L2_BLOCK_TIME;
+    uint256 public startingTimestamp;
 
     /**
      * @notice The address of the proposer;
@@ -93,49 +93,54 @@ contract L2OutputOracle is OwnableUpgradeable, Semver {
      * @custom:semver 0.0.1
      *
      * @param _submissionInterval    Interval in blocks at which checkpoints must be submitted.
-     * @param _genesisL2Output       The initial L2 output of the L2 chain.
+     * @param _l2BlockTime           The time per L2 block, in seconds.
+     * @param _startingL2Output      The initial L2 output of the L2 chain.
      * @param _startingBlockNumber   The number of the first L2 block.
      * @param _startingTimestamp     The timestamp of the first L2 block.
-     * @param _l2BlockTime           The time per L2 block, in seconds.
      * @param _proposer              The address of the proposer.
      * @param _owner                 The address of the owner.
      */
     constructor(
         uint256 _submissionInterval,
-        bytes32 _genesisL2Output,
+        uint256 _l2BlockTime,
+        bytes32 _startingL2Output,
         uint256 _startingBlockNumber,
         uint256 _startingTimestamp,
-        uint256 _l2BlockTime,
         address _proposer,
         address _owner
     ) Semver(0, 0, 1) {
-        require(
-            _startingTimestamp <= block.timestamp,
-            "L2OutputOracle: starting L2 timestamp must be less than current time"
-        );
-
         SUBMISSION_INTERVAL = _submissionInterval;
-        STARTING_BLOCK_NUMBER = _startingBlockNumber;
-        STARTING_TIMESTAMP = _startingTimestamp;
         L2_BLOCK_TIME = _l2BlockTime;
 
-        initialize(_genesisL2Output, _proposer, _owner);
+        initialize(_startingL2Output, _startingBlockNumber, _startingTimestamp, _proposer, _owner);
     }
 
     /**
      * @notice Initializer.
      *
-     * @param _genesisL2Output     The initial L2 output of the L2 chain.
+     * @param _startingL2Output    Output for the first recoded L2 block.
+     * @param _startingBlockNumber Block number for the first recoded L2 block.
+     * @param _startingTimestamp   Timestamp for the first recoded L2 block.
      * @param _proposer            The address of the proposer.
      * @param _owner               The address of the owner.
      */
     function initialize(
-        bytes32 _genesisL2Output,
+        bytes32 _startingL2Output,
+        uint256 _startingBlockNumber,
+        uint256 _startingTimestamp,
         address _proposer,
         address _owner
     ) public initializer {
-        l2Outputs[STARTING_BLOCK_NUMBER] = Types.OutputProposal(_genesisL2Output, block.timestamp);
-        latestBlockNumber = STARTING_BLOCK_NUMBER;
+        require(
+            _startingTimestamp <= block.timestamp,
+            "L2OutputOracle: starting L2 timestamp must be less than current time"
+        );
+
+        startingBlockNumber = _startingBlockNumber;
+        latestBlockNumber = _startingBlockNumber;
+        startingTimestamp = _startingTimestamp;
+        l2Outputs[startingBlockNumber] = Types.OutputProposal(_startingL2Output, block.timestamp);
+
         __Ownable_init();
         changeProposer(_proposer);
         _transferOwnership(_owner);
@@ -230,7 +235,7 @@ contract L2OutputOracle is OwnableUpgradeable, Semver {
      *         L2 block number provided is between checkpoints, this function will rerutn the next
      *         proposal for the next checkpoint.
      *         Reverts if the output proposal is either not found, or predates
-     *         the STARTING_BLOCK_NUMBER.
+     *         the startingBlockNumber.
      *
      * @param _l2BlockNumber The L2 block number of the target block.
      */
@@ -245,7 +250,7 @@ contract L2OutputOracle is OwnableUpgradeable, Semver {
         );
 
         // Find the distance between _l2BlockNumber, and the checkpoint block before it.
-        uint256 offset = (_l2BlockNumber - STARTING_BLOCK_NUMBER) % SUBMISSION_INTERVAL;
+        uint256 offset = (_l2BlockNumber - startingBlockNumber) % SUBMISSION_INTERVAL;
 
         // If the offset is zero, then the _l2BlockNumber should be checkpointed.
         // Otherwise, we'll look up the next block that will be checkpointed.
@@ -290,6 +295,6 @@ contract L2OutputOracle is OwnableUpgradeable, Semver {
      * @param _l2BlockNumber The L2 block number of the target block.
      */
     function computeL2Timestamp(uint256 _l2BlockNumber) public view returns (uint256) {
-        return STARTING_TIMESTAMP + ((_l2BlockNumber - STARTING_BLOCK_NUMBER) * L2_BLOCK_TIME);
+        return startingTimestamp + ((_l2BlockNumber - startingBlockNumber) * L2_BLOCK_TIME);
     }
 }

packages/contracts-bedrock/contracts/L1/OptimismPortal.sol

@@ -251,7 +251,7 @@ contract OptimismPortal is Initializable, ResourceMetering, Semver {
         // Ensure that the proven withdrawal's timestamp is greater than the
         // L2 Oracle's starting timestamp.
         require(
-            provenWithdrawal.timestamp >= L2_ORACLE.STARTING_TIMESTAMP(),
+            provenWithdrawal.timestamp >= L2_ORACLE.startingTimestamp(),
             "OptimismPortal: withdrawal timestamp less than L2 Oracle starting timestamp"
         );
 

packages/contracts-bedrock/contracts/deployment/BaseSystemDictator.sol

@@ -56,14 +56,22 @@ contract BaseSystemDictator is Ownable {
     }
 
     /**
-     * @notice Set of implementation addresses.
+     * @notice Fixed L2OutputOracle config.
      */
     struct L2OutputOracleConfig {
-        bytes32 l2OutputOracleGenesisL2Output;
         address l2OutputOracleProposer;
         address l2OutputOracleOwner;
     }
 
+    /**
+     * @notice Dynamic L2OutputOracle config.
+     */
+    struct L2OutputOracleDynamicConfig {
+        bytes32 l2OutputOracleStartingL2Output;
+        uint256 l2OutputOracleStartingBlockNumber;
+        uint256 l2OutputOracleStartingTimestamp;
+    }
+
     /**
      * @notice Values for the system config contract.
      */
@@ -91,11 +99,21 @@ contract BaseSystemDictator is Ownable {
      */
     DeployConfig public config;
 
+    /**
+     * @notice Dynamic configuration for the L2OutputOracle.
+     */
+    L2OutputOracleDynamicConfig public l2OutputOracleDynamicConfig;
+
     /**
      * @notice Current step;
      */
     uint8 public currentStep = 1;
 
+    /**
+     * @notice Whether or not dynamic config has been set.
+     */
+    bool public dynamicConfigSet;
+
     /**
      * @notice Checks that the current step is the expected step, then bumps the current step.
      *
@@ -114,4 +132,16 @@ contract BaseSystemDictator is Ownable {
         config = _config;
         _transferOwnership(config.globalConfig.controller);
     }
+
+    /**
+     * @notice Allows the owner to update dynamic L2OutputOracle config.
+     *
+     * @param _l2OutputOracleDynamicConfig Dynamic L2OutputOracle config.
+     */
+    function updateL2OutputOracleDynamicConfig(
+        L2OutputOracleDynamicConfig memory _l2OutputOracleDynamicConfig
+    ) external onlyOwner {
+        l2OutputOracleDynamicConfig = _l2OutputOracleDynamicConfig;
+        dynamicConfigSet = true;
+    }
 }

packages/contracts-bedrock/contracts/deployment/MigrationSystemDictator.sol

@@ -143,6 +143,12 @@ contract MigrationSystemDictator is BaseSystemDictator {
      * @notice Upgrades and initializes proxy contracts.
      */
     function step5() external onlyOwner step(5) {
+        // Dynamic config must be set before we can initialize the L2OutputOracle.
+        require(
+            dynamicConfigSet,
+            "MigrationSystemDictator: dynamic oracle config is not yet initialized"
+        );
+
         // Upgrade and initialize the L2OutputOracle.
         config.globalConfig.proxyAdmin.upgradeAndCall(
             payable(config.proxyAddressConfig.l2OutputOracleProxy),
@@ -150,7 +156,9 @@ contract MigrationSystemDictator is BaseSystemDictator {
             abi.encodeCall(
                 L2OutputOracle.initialize,
                 (
-                    config.l2OutputOracleConfig.l2OutputOracleGenesisL2Output,
+                    l2OutputOracleDynamicConfig.l2OutputOracleStartingL2Output,
+                    l2OutputOracleDynamicConfig.l2OutputOracleStartingBlockNumber,
+                    l2OutputOracleDynamicConfig.l2OutputOracleStartingTimestamp,
                     config.l2OutputOracleConfig.l2OutputOracleProposer,
                     config.l2OutputOracleConfig.l2OutputOracleOwner
                 )

packages/contracts-bedrock/contracts/test/CommonTest.t.sol

@@ -120,10 +120,10 @@ contract L2OutputOracle_Initializer is CommonTest {
         // Deploy the L2OutputOracle and transfer owernship to the proposer
         oracleImpl = new L2OutputOracle(
             submissionInterval,
+            l2BlockTime,
             genesisL2Output,
             startingBlockNumber,
             startingTimestamp,
-            l2BlockTime,
             proposer,
             owner
         );
@@ -131,7 +131,10 @@ contract L2OutputOracle_Initializer is CommonTest {
         vm.prank(multisig);
         proxy.upgradeToAndCall(
             address(oracleImpl),
-            abi.encodeCall(L2OutputOracle.initialize, (genesisL2Output, proposer, owner))
+            abi.encodeCall(
+                L2OutputOracle.initialize,
+                (genesisL2Output, startingBlockNumber, startingTimestamp, proposer, owner)
+            )
         );
         oracle = L2OutputOracle(address(proxy));
         vm.label(address(oracle), "L2OutputOracle");

packages/contracts-bedrock/contracts/test/L2OutputOracle.t.sol

@@ -18,8 +18,8 @@ contract L2OutputOracleTest is L2OutputOracle_Initializer {
         assertEq(oracle.owner(), owner);
         assertEq(oracle.SUBMISSION_INTERVAL(), submissionInterval);
         assertEq(oracle.latestBlockNumber(), startingBlockNumber);
-        assertEq(oracle.STARTING_BLOCK_NUMBER(), startingBlockNumber);
-        assertEq(oracle.STARTING_TIMESTAMP(), startingTimestamp);
+        assertEq(oracle.startingBlockNumber(), startingBlockNumber);
+        assertEq(oracle.startingTimestamp(), startingTimestamp);
         assertEq(oracle.proposer(), proposer);
         assertEq(oracle.owner(), owner);
 
@@ -33,11 +33,11 @@ contract L2OutputOracleTest is L2OutputOracle_Initializer {
 
         new L2OutputOracle(
             submissionInterval,
+            l2BlockTime,
             genesisL2Output,
             startingBlockNumber,
             // startingTimestamp is in the future
             block.timestamp + 1,
-            l2BlockTime,
             proposer,
             owner
         );
@@ -370,9 +370,9 @@ contract L2OutputOracleUpgradeable_Test is L2OutputOracle_Initializer {
 
     function test_initValuesOnProxy() external {
         assertEq(submissionInterval, oracleImpl.SUBMISSION_INTERVAL());
-        assertEq(startingBlockNumber, oracleImpl.STARTING_BLOCK_NUMBER());
-        assertEq(startingTimestamp, oracleImpl.STARTING_TIMESTAMP());
         assertEq(l2BlockTime, oracleImpl.L2_BLOCK_TIME());
+        assertEq(startingBlockNumber, oracleImpl.startingBlockNumber());
+        assertEq(startingTimestamp, oracleImpl.startingTimestamp());
 
         Types.OutputProposal memory initOutput = oracleImpl.getL2Output(startingBlockNumber);
         assertEq(genesisL2Output, initOutput.outputRoot);
@@ -384,12 +384,24 @@ contract L2OutputOracleUpgradeable_Test is L2OutputOracle_Initializer {
 
     function test_cannotInitProxy() external {
         vm.expectRevert("Initializable: contract is already initialized");
-        L2OutputOracle(payable(proxy)).initialize(genesisL2Output, proposer, owner);
+        L2OutputOracle(payable(proxy)).initialize(
+            genesisL2Output,
+            startingBlockNumber,
+            startingTimestamp,
+            proposer,
+            owner
+        );
     }
 
     function test_cannotInitImpl() external {
         vm.expectRevert("Initializable: contract is already initialized");
-        L2OutputOracle(oracleImpl).initialize(genesisL2Output, proposer, owner);
+        L2OutputOracle(oracleImpl).initialize(
+            genesisL2Output,
+            startingBlockNumber,
+            startingTimestamp,
+            proposer,
+            owner
+        );
     }
 
     function test_upgrading() external {

packages/contracts-bedrock/contracts/test/OptimismPortal.t.sol

@@ -528,10 +528,10 @@ contract OptimismPortal_FinalizeWithdrawal_Test is Portal_Initializer {
         // Warp to after the finalization period
         vm.warp(block.timestamp + op.FINALIZATION_PERIOD_SECONDS() + 1);
 
-        // Mock a STARTING_TIMESTAMP change on the L2 Oracle
+        // Mock a startingTimestamp change on the L2 Oracle
         vm.mockCall(
             address(op.L2_ORACLE()),
-            abi.encodeWithSignature("STARTING_TIMESTAMP()"),
+            abi.encodeWithSignature("startingTimestamp()"),
             abi.encode(block.timestamp + 1)
         );
 

packages/contracts-bedrock/deploy/011-L2OutputOracleImpl.ts

-import assert from 'assert'
-
 import { ethers } from 'ethers'
 import { DeployFunction } from 'hardhat-deploy/dist/types'
 import '@eth-optimism/hardhat-deploy-config'
@@ -11,30 +9,15 @@ import {
 } from '../src/deploy-utils'
 
 const deployFn: DeployFunction = async (hre) => {
-  // Use default starting time if starting time is not provided.
-  let deployL2StartingTimestamp =
-    hre.deployConfig.l2OutputOracleStartingTimestamp
-  if (deployL2StartingTimestamp < 0) {
-    const l1StartingBlock = await hre.ethers.provider.getBlock(
-      hre.deployConfig.l1StartingBlockTag
-    )
-    if (l1StartingBlock === null) {
-      throw new Error(
-        `Cannot fetch block tag ${hre.deployConfig.l1StartingBlockTag}`
-      )
-    }
-    deployL2StartingTimestamp = l1StartingBlock.timestamp
-  }
-
   await deployAndVerifyAndThen({
     hre,
     name: 'L2OutputOracle',
     args: [
       hre.deployConfig.l2OutputOracleSubmissionInterval,
-      hre.deployConfig.l2OutputOracleGenesisL2Output,
-      hre.deployConfig.l2OutputOracleStartingBlockNumber,
-      deployL2StartingTimestamp,
       hre.deployConfig.l2BlockTime,
+      ethers.constants.HashZero,
+      0,
+      0,
       hre.deployConfig.l2OutputOracleProposer,
       hre.deployConfig.l2OutputOracleOwner,
     ],
@@ -44,16 +27,6 @@ const deployFn: DeployFunction = async (hre) => {
         'SUBMISSION_INTERVAL',
         hre.deployConfig.l2OutputOracleSubmissionInterval
       )
-      await assertContractVariable(
-        contract,
-        'STARTING_BLOCK_NUMBER',
-        hre.deployConfig.l2OutputOracleStartingBlockNumber
-      )
-      await assertContractVariable(
-        contract,
-        'STARTING_TIMESTAMP',
-        deployL2StartingTimestamp
-      )
       await assertContractVariable(
         contract,
         'L2_BLOCK_TIME',
@@ -69,24 +42,6 @@ const deployFn: DeployFunction = async (hre) => {
         'owner',
         hre.deployConfig.l2OutputOracleOwner
       )
-
-      // Has to be done separately since l2Output is a mapping.
-      if (
-        hre.deployConfig.l2OutputOracleGenesisL2Output ===
-        ethers.constants.HashZero
-      ) {
-        console.log(
-          `[WARNING] Genesis L2 output is ZERO and should NOT BE ZERO if you are deploying to prod`
-        )
-      } else {
-        const output = await contract.getL2Output(
-          hre.deployConfig.l2OutputOracleStartingBlockNumber
-        )
-        assert(
-          output.outputRoot === hre.deployConfig.l2OutputOracleGenesisL2Output,
-          `[FATAL] L2OutputOracleImpl genesis output is ${output.outputRoot} but should be ${hre.deployConfig.l2OutputOracleGenesisL2Output}`
-        )
-      }
     },
   })
 }

packages/contracts-bedrock/src/deploy-utils.ts

@@ -32,7 +32,6 @@ export interface DictatorConfig {
     systemConfigImpl: string
   }
   l2OutputOracleConfig: {
-    l2OutputOracleGenesisL2Output: string
     l2OutputOracleProposer: string
     l2OutputOracleOwner: string
   }
@@ -352,8 +351,6 @@ export const makeDictatorConfig = async (
       systemConfigImpl: await getDeploymentAddress(hre, 'SystemConfig'),
     },
     l2OutputOracleConfig: {
-      l2OutputOracleGenesisL2Output:
-        hre.deployConfig.l2OutputOracleGenesisL2Output,
       l2OutputOracleProposer: hre.deployConfig.l2OutputOracleProposer,
       l2OutputOracleOwner: hre.deployConfig.l2OutputOracleOwner,
     },

packages/sdk/src/cross-chain-messenger.ts

@@ -236,13 +236,24 @@ export class CrossChainMessenger {
       return this._l2OutputOracleParameters
     }
 
+    // Temporary logic to support legacy Bedrock testnets.
+    // TODO: Remove this once all legacy testnets are deprecated.
+    let startingBlockNumber: number
+    try {
+      startingBlockNumber = (
+        await this.contracts.l1.L2OutputOracle.startingBlockNumber()
+      ).toNumber()
+    } catch {
+      startingBlockNumber = (
+        await this.contracts.l1.L2OutputOracle.STARTING_BLOCK_NUMBER()
+      ).toNumber()
+    }
+
     this._l2OutputOracleParameters = {
+      startingBlockNumber,
       submissionInterval: (
         await this.contracts.l1.L2OutputOracle.SUBMISSION_INTERVAL()
       ).toNumber(),
-      startingBlockNumber: (
-        await this.contracts.l1.L2OutputOracle.STARTING_BLOCK_NUMBER()
-      ).toNumber(),
       l2BlockTime: (
         await this.contracts.l1.L2OutputOracle.L2_BLOCK_TIME()
       ).toNumber(),